Chamber cleaning device and method

ABSTRACT

A CHAMBER CLEANING DEVICE AND METHOD WHEREIN THE DEVICE HAS A ROTATABLE MEMBER WITHIN THE CHAMBER, AND PENDENT FROM THE ROTATABLE MEMBER ONE OR MORE FLEXIBLE CHAIN MEMBERS WHICH ARE CAUSED TO CONTACT THE INTERNAL SURFACES OF THE CHAMBER ON A ROTATION OF THE ROTATABLE MEMBER. THE CONTACTING OF THE FLEXIBLE CHAIN MEMBER WITH THE INTERNAL SURFACES OF THE CHAMBER EFFECTIVELY REMOVES ADHERING SUBSTANCES FROM THESE SURFACES BY BOTH A RAP PING AND FRICTION SCRAPING OF THE INTERNAL CHAMBER SURFACES.

July 25, 1972 A. A. ZIMMER CHAMBER CLEANING DEVICE AND METHOD 2 Sheets-Sheet 1 Filed Aug. 20, 1970 INVENTOR AUST/N A. Z/MMER M if A T TORNFV y 25, 1972 A. A. ZIMMER 3,679,477

CHAMBER CLEANING DEVICE AND METHOD Filed Aug. 20, 1970 2 Sheets-Sheet 2 INVENTOR AUSTIN A. Z/MMER BY @M 2W ATTORNEY FIG. 2

United States Patent O 3,679,477 CHAMBER CLEANING DEVICE AND METHOD Austin A. Zimmer, Elkridge, Md., assiguor to W. R. Grace & Co. Filed Aug. 20, 1970, Ser. No. 65,405 Int. Cl. B08b 9/00 US. Cl. 134-8 19 Claims ABSTRACT OF THE DISCLOSURE A chamber cleaning device and method wherein the device has a rotatable member within the chamber, and pendent from the rotatable member one or more flexible chain members which are caused to contact the internal surfaces of the chamber on a rotation of the rotatable member. The contacting of the flexible chain member with the internal surfaces of the chamber effectively removes adhering substances from these surfaces by both a rapping and friction scraping of the internal chamber surfaces BACKGROUND OF THE INVENTION This invention relates to cleaning devices for concurrently removing substances which tend to adhere to the inner surfaces of process chambers, while the chamber is in productive opertaion. In a specific view, the present invention relates to a chamber cleaning device whereby flexible chains are made to contact the inner surfaces of the chamber and remove any material which adheres to the inner surface, thereby obviating any process shutdown to permit a manual or semi-manual cleaning of the chamber. The manufacturing arts are constantly concerned by scale or other buildup on the interior surfaces of process chamber and vessel which decreases the overall efiiciency of the process. The buildup of adhering material on the internal surfaces of chambers decreases the effective volume of the chamber, as well as changing the heat transfer and other properties of the chamber. In many processes, this buildup on the internal surfaces of chambers where a process is in continuous operation requires duplicate equipment which can be used while one is being cleaned. It is obvious that this has many disadvantages and is undesirable in many ways.

The prior art does not disclose the use of flexible chains or other devices for concurrent chamber cleaning and operational use. The present invention, in solving this problem, allows a chamber to be continuously cleaned as it is in operation. In the chemical and related industries, this obviates costly shutdowns, as well as permits optimum use of plant equipment. Some patents of relevance to the present invention includes US. Pat. No. 2,465,921, US. Pat. No. 3,343,986 and US. Pat. No. 3,381,419. US. Pat. 2,465,921 discloses a device for cleaning flues; this includes the use of brushes or chains. The device is inserted into the flue and operated to remove adhering particles. This device is not a part of the flue while the flue is in actual operation. US. Pat. 3,434,986 comprises the use of flailing chains to remove flash from a casting. There is no chamber involved in this device. And US. Pat. 3,381,- 419 consists of a cylinder deglazing tool that is essentially an abraiding device which, by a grinding, removes glazing from a cylinder wall. These patents fail to disclose a chain chamber scraping and cleaning device, and particularly one that is an integral part of the chamber and which 3,679,477 Patented July 25, 1972 "ice removes sidewall adhering particles during operational use of the chamber for its prime function.

A particular and prime use of the present invention is in continuously maintaining aluminum chloride condenser chambers in a usable condition with no down time for condenser cleaning. By the use of the device of the present invention, the condenser chamber is continuously or intermittently cleaned. In aluminum chloride production, aluminum metal is contacted with chlorine gas at an elevated tempertaure in a reaction chamber. Vaporous aluminum chloride is produced which is then fed to a condenser chamber so that it can be solidified and collected. The aluminum chloride solidifies mainly by crystallization on the cooler internal surfaces of this condenser chamber. Presently these aluminum chloride crystals are removed from the condenser either by a condenser shutdown and a manual cleaning, or in a semicontinuous method by manually rapping the outside surface with a hammer to continually remove some of the crystalline aluminum chloride with a condenser shutdown for a complete removal. The disadvantages to either process are obvious. Down time and necessary duplicate equipment are some. A further and serious problem is that more plant personnel are necessary, and these people must be subject to a high chlorine environment. This is a dangerous and objectionable job which it is difficult to find people willing to perform. The device of the present invention overcomes these disadvantages and solves the problem. This invention allows the collection of the aluminum chloride in a continuous manner without the requirement of period shutdowns, duplicate equipment or endangerment of plant personnel. Further, the device of this invention in maintaining the internal surfaces clean does not grind down or otherwise effect the crystalline nature of the aluminum chloride product, but removes the crystals in essentially their original crystalline form as condensed in the chamber.

It is an object of this invention to set out a chamber cleaning device and a method for use of this device.

It is also an object of this invention to illustrate a device capable of rapping and scraping to clean a chamber while the chamber is in operational use.

It is further an object of this invention to set out a chamber rapping and scraping device which, by the use of fully flexible chains or semi-flexible chains, these chains can be operated to clean the internal surfaces and parts of a chamber while the chamber is in operational use.

It is another object of this invention to set out a device for maintaining aluminum chloride condenser chambers in continuous use by continuously or intermittently cleaning the internal surfaces and parts by a rapping and scraping while still maintaining the crystalline integrity of the product.

BRIEF SUMMARY OF THE INVENTION This invention comprises a device that is an integral part of a chamber and which cleans the internal surfaces by rapping and scraping the internal surfaces of the chamber while the chamber is in operational use; and the method for use of this device. The chamber scraping device comprises a chamber having a rotatable member mounted within said chamber and flexible members pendent from said rotatable member whereby on rotation of said rotatable member, said flexible members contact and rap and scrape the inner surfaces of said chamber. In a preferred structural embodiment, the flexible members are chain sections. In a preferred use embodiment, the chamber is an aluminum chloride condenser.

BRIEF DESCRIPTION OF THE DRAWINGS chamber.

DETAILED DESCRIPTION OF THE (INVENTION Broadly, this invention comprises a means for cleaning the internal surfaces of a process chamber or vessel concurrently while the chamber or vessel is in prime function operation. By prime function operation is meant that function the chamber or vessel is designed to accomplish in a designated process. By use of the present device, the side walls and internal parts can be constantly rapped and scraped, thereby cleaning and maintaining the original volume and other operational characteristics of the chamber or vessel. Although designed principally for air-solid systems, the scraper device of this invention is also useful with liquid-solid systems. Exemplary air-solid systems include mixing chambers, drying chambers, material transfer chambers, condensers and hoppers. In a particular embodiment, this invention comprises a means for continuously or intermittently cleaning aluminum chloride condenser chambers. By the use of this cleaning means, the chamber can be kept in indefinite continuous operation, and this cleaning means does not affect the crystalline integrity of the aluminum chloride product.

The invention will be more fully amplified with reference being made to the appended drawings. FIG. 1 sets out a schematic view of essentially cylindrical chamber consisting of sidewall 11, top section 12 and bottom valve portion 14. Sidewall -11 has an opening for receiving materials. The bottom portion consists of a valved opening 14 for gravity delivery of materials. Top section 12 consists of opening 13 for venting or further delivery of materials and a central opening 24 which serves to mount rotatable shaft and provide for con nection to the rotating drive means. The lower portion of shaft 20 is rotatably mounted in suitable bearing 23. The drive means may be of any conventional type. In the present embodiment, it consists of electric motor 16 supported by beam '19 and interconnected to a transmission 18 via belt or chain 17.

In the particular and preferred mode, this invention is an integral part of an aluminum chloride condenser chamber. Vaporous aluminum chloride is passed from a reactor into a cooling condenser chamber. The aluminum chloride crystallizes and collects on the cool surfaces of the chamber. Approximately at least every 1'5 to 60 minutes, the shaft 20 is rotated and the chains are caused to rap and scrape the internal surfaces. This rotation is continued for from 2 to 10 minutes. Rotation may be continued for a longer period if necessary. The aluminum chloride crystals dislodged and cleaned from the surface are then collected at the hopper end of the chamber. It has been folmd that a continuous rotation of shaft 20 is not necessary with intermittent rotation being suflicient for cleaning.

In operation when the essentially vertical shaft 20 is rotated, essentially horizontal shafts 2 1 and '22, which are fixedly and rigidly mounted to shaft 20, rotate causing the flexible chains 26-29, which are interconnected to essentially horizontal shafts 21 and 23 by connecting means 25, to extend wall 11, and rap and scrape wall 11. In this embodiment, one of the flexible chains consists of a chain configuration 26 with a rigid section 27 and a further chain configuration 28. The rigid section 27 serves to prevent entangling in sidewall opening 15. Further in this embodiment, the chains are attached at one end to essentially horizontal shaft 21 and at the other end to essentially horizontal shaft 22. This is one embodiment, but it is not necessary that there be a lower connection to essentially horizontal shaft 22. 'In other words, the chain configuration 26-28 may be sinn'lar to that of chain configuration 29 which is pendent from essentially horizontal shaft 22 and having no lower end connection. Chains 29 clean the shaped hopper area.

FIG. 2 sets out a chamber with scraper device wherein the chamber is cylindrical and the vertical shaft 20 extends from the cylinder top 12 to a shaft support 31 which carries bearing 23. Valve opening 14 is for delivery of contained material. Further, this embodiment discloses the variation wherein flexible members 29 can be secured at both ends. An additional essentially horizontal shaft 33 is added to secure the lower chains 32. Chains 32 here clean the hopper area. This figure further sets out the use of pendent flexible chains 30 form the vertical shaft 20. In this mode, when the shaft 20 is rotated, these chains will rap and scrape shaft 20 and to a lesser degree horizontal shaft 22 and shaft support 31, thereby removing any adhering material.

FIGS. 3 and 4 set out end elevational views of various embodiments of the rotatable shaft within the chamber. In FIG. 3, the essentially vertical shaft 20 has six rigidly mounted essentially horizontal shafts and adjacent to the wall 11 are mounted the flexible chains. In FIG. 4, there are two essentially horizontal shafts. In actual operation, there may be from one to eight or more shafts, but for practical purposes from two to six are preferred.

Further, there is no requirement that these essentially horizontal shafts 21, or other essentially horizontal shafts all be at the same fixed level in one or more defined configurations. These may range from the defined configurations of FIGS. 3-4 to completely random configurations. In essence, any configuration is operable as long as the pendent chains will contact and rap and scrape the inner surfaces and parts of the chamber on rotation of shaft 20.

FIGS. 5-8 illustrate various embodiments of the pendent flexible chains. Segment 25 is the attachment means for connection to the essentially horizontal shafts. Various configurations and networks of chains are operable and useful. FIG. 6 in a further illustration shows side bars 34 on chain links. These bars serve to increase the life of the chain links which contact the chamber inner walls. FIG. 7 sets out a further complex chain link network, and FIG. 8 a metal piece 35 to provide for a lengthened wall contact. Still other variations are possible and within the skill of those in the art.

In general, the chamber itself, shafts and other parts can be constructed out of metal, wood, plastic, etc. In most uses, such chambers and shafts are metal, usually a steel or aluminum. The flexible members or chains are preferably metal, but other materials could be used. Using metal parts has the advantage of maintaining all parts at one potential (grounded), thus reducing the possibility of static spark discharges which could cause serious hazards in the handling of powdered materials. One further consideration is that the materials of construction of the chamber and cleaning device must be compatible with the substances with which they will be contacted.

The size of the chamber is strictly dependent on the need of the user. The chamber should be essentially cylindrical and may be of a diameter of from less than one foot to greater than ten feet. The height may further range from one foot to twenty feet or more. The speed of rotation of shaft 20 may be from 1 revolution per minute (r.pm.) to 100 r.p.m. or more. All that is essential is that a speed be used so that the centrifugal force or rotation will force the chain members to rap and scrape against the inner chamber wall surfaces. The number, size, weight and so on of the flexible chain members will be governed by the need, as well as the size and shape of the chamber, speed of rotation, and the type of material that is being rapped and scraped from the inner surface. The chains operably can be of one of the types known as welded link steel of the type used for drag lines and hoists. The links have an O.D. (outside diameter) of from 1 inch to 6 inches or more, and an ID. (inside diameter) of from /2 inch to 5 inches or more. An individual link has a weight of from 1 ounce to 2 pounds or more.

Further, the transmission 18 may be of a type that either solely produces a speed ratio change, or one that will periodically alternate the direction of rotation. The change in direction may occur within a single rotation of the shaft or after any set number of rotations. The ultimate aim is to generate both a rapping and scraping of the internal chamber surfaces and parts.

The following examples are set out to further amplify the present invention.

EXAMPLE I This example illustrates the use of the cleaning device in an aluminum chloride condenser chamber.

A closed reactor is charged with molten aluminum. The reactor is operated at 1200 to 1400 F. and anhydrous chloride gas is fed at a rate of 3 pounds of chlorine and one part aluminum into the molten aluminum furnace. The reaction is continuous, with aluminum and chlorine continually being added. The heat of reaction is sufiicient to maintain the aluminum in a molten bath. Vaporous aluminum chloride is evolved from the bath surface and is fed by a closed conduit to a condenser chamber essentially as FIG. 2. This chamber has a height of 20 feet and a diameter of 8 feet. The opening 15 is 24 inches with the hopper opening being 15 inches. The vaporous aluminum chloride enters chamber via opening 15. The Vaporous aluminum chloride condenses and crystallizes on the chamber inner surfaces. After 240 minutes of operation, the shaft 20 is rotated at 50 r.p.m. (revolutions per minute), causing chains 28 and 29 to rap and scrape the inner wall surfaces. Chains 20 rap and scrape the shafts 20, 22 and 31. This rapping and scraping removes the adhering aluminum chloride in a crystalline form. After 3 minutes, the rotation of shaft 20 is stopped, but feed from the reactor continues (this operation is repeated in another 120 minutes). The dislodged crystalline aluminum chloride is collected via the hopper opening 14.

EXAMPLE II The same condenser chamber is utilized as in Example 1 except that two aluminum chloride reactors are fed into this condenser. In order to accommodate for the greater input to the condenser, the shaft is rotated at 50 r.p.m. at 60 minute intervals instead of at 120 minute intervals as in Example I. The crystalline aluminum chloride is recovered as in Example I.

EXAMPLE III The procedure of Example II is repeated, except that the direction of rotation of the shaft 20 alternates every minute. This causes an increase in the rapping of the internal wall surfaces and of the shaft itself. There is good recovery of the crystalline aluminum chloride.

Further embodiments, variations and uses will be obvious to those of skill in the art, once informed by this disclosure. This invention can be adapted to any system wherein a concurrent operation and scraping or cleaning is desired.

I claim:

1. A cleaning device for removing adhering material from the internal surfaces of an essentially vertical cylindrical chamber comprising:

a vertical rotatable member centrally mounted on the major axis within said chamber,

a plurality of rigid horizontal members fixedly attached to said vertical rotatable member, equal numbers of said horizontal members being fixedly attached to an upper section and a lower section of said vertical rotatable member, and

flexible members attached at one end to an end of an upper horizontal member, and at another end to and end of a lower horizontal member whereby on rotation of said vertical rotatable member said flexible members extend outwardly and rap and scrape the inner surfaces of said chamber to remove adhering material.

2. .A chamber cleaning device as in claim 1 wherein said essentially vertical member is connected at one end to a rotating means.

3. A chamber cleaning device as in claim 1 wherein there is at least one pendent flexible member from said essentially vehicle member.

4. A chamber cleaning device as in claim 1 wherein a portion of said flexible members are comprised of rigid sections whereby the flexible members are made to clear any chamber sidewall apertures.

5. A chamber cleaning device as in claim 1 wherein there are at least eight essentially horizontal members.

6. A chamber cleaning device as in claim 5 wherein said flexible members comprise chains.

7. A chamber cleaning device as in claim 1 wherein flexible members are pendent from said horizontal members fixedly attached to a lower section of said vertical rotatable member.

8. A chamber cleaning device as in claim 7 wherein said flexible members are chains.

9. A chamber cleaning device as in claim 1 wherein there are at least four essentially horizontal members.

10. A chamber cleaning device as in claim 9 wherein said flexible members comprise chains.

11. A chamber cleaning device as in claim 10 wherein said chains comprise an interconnected network of chains.

12. The method of cleaning the internal surfaces of a vertical essentially cylindrical aluminum chloride condenser chamber comprising:

rotating an essentially vertical rotatable shaft mounted within said chamber along the major axis of said chamber, said vertical rotatable shaft having a plurality of rigid horizontal members fixedly attached to said vertical rotatable shaft, equal numbers of said horizontal members being fixedly attached to an upper section and a lower section of said vertical rotatable shaft, and flexible chains attached at one end to an upper horizontal member and at the other end to a lower horizontal member, whereby the flexible chains rap and scrape the chamber wall, thereby removing adhering aluminum chloride.

13. The method of claim 12. wherein two or more reactor vessels feed into said condenser chamber.

14. The method of claim 12 wherein said essentially vertical rotatable shaft is rotated continuously.

15. The method of claim 12 wherein there are at least four horizontal fixedly mounted members.

16. The method of claim 15 wherein said flexible chains comprise an interconnected network of chains.

17. The method of claim 12 wherein said essentially vertical rotatable shaft is rotated intermittently.

18. The method of claim 17 wherein the direction of rotation changes at least once during each intermittent period.

7 8 19. The method of claim 17 wherein said essentially 2,228,421 1/1941 Taylor 15,--104.14 UX vertical rotatable shaft is rotated about every 60 minutes 2,319,985 5/1943 Genasci 15-93 X for a period of 4 minutes. Y

I FOREIGN PATENTS References Cited 5 447,031 3/1968 Switzerland 15246.5 UNITED STATES PATENTS 7 962,370 6/1910 Malick 1s-104.14 UX MORRIS WOLK Pnmary Examme 1,349,817 8/ 1920 Coast 15104.10 UX J. T. ZATARGA, Assistant Examiner 1,515,410 11/1924 Renner 15-10414 UX 10 1,621,417 3/1927 Knapp 1558 X X- 1,682,735 9/1928 Bergerioux 15104.10'U X 15 24 5; 134 22; 1 5 95 1,898,201 2/1933 MOrrOW 15--104.14 UX 

